The major histocompatibility complex (MHC) in humans is known as human leukocyte antigen (HLA). HLA molecules are critically involved in antigen presentation and immune responses. HLA-B*27 is a particular HLA allele associated with a high incidence of ankylosing spondylitis and other seronegative spondyloarthropathies.
HLA class 1 molecules such as HLA-B*27 consist of two chains: a membrane-bound heavy chain consisting of three Ig-domains (alpha-1, alpha-2 and alpha-3), and a non-covalently-associated common light chain known as beta-2-microglobulin (β2m). Several allelic subtypes of HLA-B*27 exist, including HLA-B*2701 through HLA-B*2728. Sequence differences between HLA alleles are mostly confined to the peptide-binding cleft between the alpha-1 and alpha-2 domains of the heavy chain. Presentation of peptides of intracellular origin (self- or viral peptides) in the context of HLA-B*27 leads to activation of HLA-restricted T cell clones expressing T cell receptors (TCR) specific for the particular peptide.
Antibodies against HLA-B*27 are generally known in the art, but are mainly described for use in diagnostic and/or detection applications. (See, e.g., U.S. Pat. No. 5,369,010, and Urban et al., Proc. Natl. Acad. Sci. USA 91:1534-1538 (1994)). Thus, a need exists in the art for new, high-affinity binding anti-HLA-B*27 antibodies that are suitable for therapeutic applications and other utilities.